package net.contrend.util;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class CharacterEncodingFilter implements Filter {

    protected String encoding = null;
    protected FilterConfig filterConfig = null;
    protected boolean ignore = true;

    public void destroy() {
        this.encoding = null;
        this.filterConfig = null;
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        if (this.ignore || (request.getCharacterEncoding() == null)) {
            if (this.encoding != null) {
                request.setCharacterEncoding(encoding);
            }
        }
        chain.doFilter(request, response);
    }

    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
        this.encoding = filterConfig.getInitParameter("encoding");
        
        String value = filterConfig.getInitParameter("ignore");
        if (value == null || value.equalsIgnoreCase("true") || value.equalsIgnoreCase("yes")) {
            this.ignore = true;
        } else {
            this.ignore = false;
        }
    }
}
